| 摘要 |
PURPOSE:To provide a drawing device capable of drawing a preform base material for optical fiber in high accuracy without curving the base material. CONSTITUTION:A lifting and lowering device 20 which holds an upper end part of a preform base material 2 for optical fiber passing through passage of the heating furnace 10 and can lift and lower the base material 2 is arranged above the heating furnace having vertical passage. Plural pairs of taking-off units 30 and 40 consisting of a pair of driving rollers 32 and 42 for taking off the base material 2 downward vertically while pressing on the side of the base material 2 and rotating and outside diameter measuring devices 31 and 41 for measuring the outside of the preform base material 2 closer to the heating furnace side than these driving rollers 32 and 42 are arranged along the course of the preform, base material 2. These driving rollers 32 and 42 can be separated from the preform base material 2 every each take-off units 30 and 40. |
